1. Field of the Invention
This invention relates to a master component for simulating the flow through a component of a gas turbine engine. The invention relates to a master component for simulating the flow through an aerofoil element of a gas turbine engine, for use in flow calibration.
2. Description of the Related Art
The gas turbine engine is a highly sophisticated and complex device which depends upon all the component parts achieving their respective levels of performance to achieve the design targets, for example in terms of life and cost of ownership. Overall engine performance is evaluated immediately prior to delivery to the customer and during main engine development testing. However, various components and systems need to be evaluated (for example tested and/or proven) prior to engine installation. System/component performance evaluation consists of many facets. An important aspect of the evaluation relates to the specified air flow through and/or around the components being evaluated.
Typically, evaluation of components and systems may be performed at a number of different test facilities. These different test facilities may be geographically separate from each other. The different test facilities must have consistent performance relative to each other, for example in order to enable tests conducted at different test facilities to be used to compare different systems and/or components.
In order to assess system consistency, and to allow comparisons between test facilities where required, master components, which may be referred to as calibration components, are used.
Typically, a master component is simply a component has the same geometry as the design component (or design baseline component), and is calibrated by a suitable approved facility. The component may be a scrap part but the system geometry and performance is typically to the design specification.
Once the master component has been calibrated by a suitable approved facility, it is then sent to a test facility, where it has to perform the same as in the approved facility (e.g. in terms of flow) to within an agreed tolerance. Once this has been achieved, the master component is used at regular intervals to ensure that the facility is performing in a stable manner.
The master component is thus intended to be used to check for any variation in the performance of the test facility itself. However, it has been found that conventional master components, which are simply dedicated components that have the same geometry as the design component, exhibit variation in performance over time. This means that it is not possible to determine whether any variation in performance is a result of variation in the performance of the test facility or variation in the performance of the master component itself.